3.已知如圖,長(zhǎng)方形ABCD中,AB=5,P為BC上一個(gè)動(dòng)點(diǎn),BP=m,點(diǎn)B關(guān)于直線(xiàn)AP的對(duì)稱(chēng)點(diǎn)是點(diǎn)E.
(1)當(dāng)m=2時(shí),若直線(xiàn)PE恰好經(jīng)過(guò)點(diǎn)D,求此時(shí)AD的長(zhǎng);
(2)若AD足夠長(zhǎng),當(dāng)點(diǎn)E到直線(xiàn)AD的距離不超過(guò)3時(shí),求m的取值范圍.
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